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Victor
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You can copy and paste the list from the error message into Edit -> Select nodes by number. In case of the CCX solver, there are buttons Select nodes and Select elements in the Details window to do that.
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As @disla said, use Gmsh. It solves a lot of mysterious meshing failures. The only reason it's not the default or even the only mesher is that it's free software with a capital "f" so it doesn't want Mecway peeing in its sandpit.
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@disla, could you elaborate a bit on how you'd use this proposed feature? I imagine something like: * Select some faces * Add the node at the centroid * Put node-surface coupling on them * Then what? I don't thing there's much you can do wi…
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@Sergio, I feel that having a lot of specific pre-defined shapes could become a bit of an anti-feature if it gets big enough that it's hard to know if it contains what you want or not. The existing plate meshes are actually generated by a general pu…
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Inner radius is for the central hole and those shapes don't have a hole. You can make a hole by using Mesh tools -> Hole on the central node afterwards. Plate mesh is a legacy feature that I've maintained mainly to not lose functionality, but ha…
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@disla, not sure if Gmsh identifies the separate parts. If it does, perhaps I can get Mecway to read that information. But I wonder if that code Sergio posted merges it all into one homogeneous thing?
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Thanks @disla, that's impressive, especially confirming very large rotations which are often a problem. Took me a long time to work it out too but seems like the core principle is exploiting the fact that CCX uses translational DOFs to represent rot…
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Happy to have passively helped
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Hello Ken I think the easiest way for axial symmetry and nonlinear through Mecway is the thin wedge. Enforce symmetry using elastic support with a high normal stiffness and zero tangential stiffness so it behaves like frictionless support which is …
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I don't know an accurate way to model tightening torque. I would imagine applying a fixed rotation angle to the bolt and constraining the nut against rotation after it is tensioned but not sure how valid that is. Other than torque, put contacts bet…
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Thanks for reporting this bug. It happens on big models with a high ratio of external to internal element faces because Mecway uses the total number of faces to estimate what texture resolution to use and it assumes that most of them will be invisib…
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Use the CCX solver (Analysis settings -> Solver). With the internal solver, bonded contact is always rigid in the thickness direction.
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I'm not sure. It looks like a problem reading a file, maybe the solution data from CCX. Does it happens at the end of a CCX solve? Is there any other information in the error message? Also, is this Mecway version 14 and if CCX, what version of that?
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I think it's the longest dimension of the element, or something close to that. I usually pick a value around 1-10 times the minimum wall thickness to prevent extremely flat elements which seem to cause meshing failures. You're right that for the bes…
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Not something to worry about. When CCX expands shells to solids, it sometimes joins them together with shared nodes as you'd expect but sometimes it separates them and connects them with MPCs so they're disconnected in the mesh but still connected m…
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It meshes OK if you set Maximum element size to 10 mm. This seems to be necessary with thin-walled parts sometimes.
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I had a look at section 4.5.1/2/3 and it seems to really depend on the the element formulation being no better or worse than what they expect. Perhaps this is why only approved software is allowed? I was going to suggest refining the mesh to create …
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Not sure if this would help, but are you aware of OUTPUT=2D on *NODE FILE or *EL FILE? It causes shells remain as 2D elements in the solution and CCX averages the stresses from the 3D nodes into 2D, which loses information like bending stress but sh…
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Thanks John. Fantastic idea.
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No, sorry. The file format is defined by the code that generates it which is not organized to make generating a complete definition easy.
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@cashan Those are indeed limitations. I looked into beam offset once but somehow didn't implement it. Perhaps it was too difficult. Just one other suggestion - there is shell offset which you might be able to use instead of all the stiffeners have …
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Regarding beam elements. Mecway isn't much better than LISA in that area. Though it allows L-section beams, they have the limitation of no bending-twisting coupling, which I think may be the same as LISA. The tools for manually building plate meshe…
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Yes, it's a regression when the solution has more elements than the model, sorry. * In v13, additional elements would end up in some arbitrary component and fewer elements would cause a crash. * In v14, both additional and fewer elements cause …
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Not automatically. But I guess you know that you can do each time step one by one? Whichever time step is currently shown in the solution is where the temperatures are taken from.
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Mecway doesn't output values at integration points, but CCX does with the .dat file (*EL PRINT). I suppose another way would be to interpolate the node values back to the Gauss points using element shape functions. Though I don't know anything abo…
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Not with the solution formula since it treats the fields as continuous and evaluated at the nodes so element volume wouldn't really make sense. However, the Python API gives access to individual element volumes as well as the integral tool, all fie…
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Heaviside being greater than 1 (or less than 0) inside quadratic elements at transitions between compression and tension is a consequence of the quadratic elements representing the step function with a quadratic one. The mean and integral tools also…
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Is m also a constant? If so, you could make a new field variable for the integrand using Solution -> New formula then use the integral tool (Solution -> Volume integral) to integrate that over volume. That way , you don't need to know individu…
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Since Poisson effect is happening, I'd expect greater stress and plastic strain in tension due to the reduced cross-section area. The curve describes both tension and compression symmetrically since it uses von Mises equivalent stress and a similar…
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Oh, I understand now. It's only undergoing tension (or compression) with no load reversal so the two hardening models should be equivalent in that region. I don't understand the theory here so I'm not sure if Poisson's ratio is supposed to remain c…
